An output control unit controls a drive terminal for a BEMF detection object phase to a high-impedance state in a mask term. A BEMF detection unit detects a voltage of the drive terminal for the detection object phase when a center tap voltage is set as a reference as BEMF in a PWM on-term for remaining two phases per PWM period in the mask term and asserts a zero-crossing signal when the voltage is reduced to zero. A PWM fixing unit fixes the remaining two phases to the PWM on-terms in a first term from a predetermined timing after an amplitude level of BEMF becomes smaller than a BEMF threshold amplitude to assertion of the zero-crossing signal. The BEMF detection unit continuously detects BEMF in the first term.

A method of controlling an electric oil pump driven by a motor, may include changing, by a controller, a frequency of a current applied to the motor with a predetermined control cycle to control RPM of the motor to instantaneously change into a different value according to a frequency change.

To solve the problem of multi-pulse control in which the load of the control software is increased and further switching/timing adjustment is required, a semiconductor device includes a control unit including a CPU and a memory, a PWM output circuit for controlling the driver IC to drive the power semiconductor device, a current detection circuit for detecting the motor current, and an angle detection circuit for detecting the angle of the motor. The PWM output circuit includes a square wave generator circuit to generate a square wave based on the angle of the angle detection circuit as well as the base square wave information.

A valve control device includes a drive circuit for supplying a drive signal to an actuator adjusting an opening degree of a valve via a prescribed transmission line, generates a PWM signal on the basis of a target opening degree supplied from the outside and a sensor signal that indicates a real opening degree of the valve, and supplies the PWM signal to the drive circuit. The valve control device includes a disconnection detection unit which detects, on the basis of the PWM signal and a monitor signal of the drive signal, whether the transmission line is disconnected.

A control device stores a plurality of operation patterns associated with each of synchronous numbers and modulation factors, and the synchronous numbers each define the upper limit of the number of switching operations for each switch constituting an inverter. The control device selects an appropriate operation pattern from among the stored operation patterns, and operates each switch on the basis of the selected operation pattern. The control device stores a plurality of operation patterns associated with the same modulation factor for the same synchronous number. In a case where there is a plurality of next patterns as operation patterns corresponding to a next modulation factor, the control device selects, from among the next patterns, an operation pattern with a small change from a currently set operation pattern.

A control device is applied for a power supply system that includes two boost converters. The two boost converters boosts inputted direct-current voltages to predetermined output voltages and output ends of the two boost converters are connected in parallel with each other. The control device includes a switching portion and a control portion. The switching portion controls switching of a switching element included in each of the two boost converters. The control portion shifts switching timings of the switching elements of the two boost converters from each other.

In one embodiment, electronic circuitry includes a reference circuit configured to generate a reference pulse signal synchronized with a clock signal on the basis of an input pulse signal, a delay circuit configured to delay the reference pulse signal and generate a delayed pulse signal, and an output circuit configured to output a pulse train including a plurality of pulses synchronized with the clock signal on the basis of the reference pulse signal and the delayed pulse signal, and the clock signal.

A high-integrity electromechanical actuator control system includes a system function controller, a plurality of actuator controllers, and at least one electromechanical actuator. Each actuator controller includes a primary channel having a first controller, a second controller, and a duty cycle computation circuit, and includes a backup channel having a backup controller. The first controller receives digital actuator control commands from two functional control channels and supplies first digital duty cycle commands. The second controller receives digital actuator control commands from two functional control channels and supplies second digital duty cycle commands. The duty cycle computation circuit computes an average of the first and second duty cycle commands and generates pulse width modulated (PWM) commutation control signals based on the computed average. The backup controller receives digital actuator control commands from two different functional control channels and generates and supplies backup PWM commutation control signals.

A motor drive controller capable of taking measures against vibration or noise of a motor is provided. The motor drive controller configured to drive a stepping motor in microstepping mode controls the number of PWM (Pulse Width Modulation) cycles contained in one microstep cycle. More specifically, the number of PWM cycles contained in one microstep cycle is controlled so that a vibration contained in a current waveform determined by the number of PWM cycles contained in one microstep cycle does not approximate the natural frequency of the stepping motor.

In accordance with one aspect of the present disclosure, a motor drive control device is a motor drive control device performing PWM (Pulse Width Modulation) control of a motor, wherein harmonics of a fundamental frequency for PWM control of the motor are included in noise occurring from the motor; the fundamental frequency for PWM control is larger than a frequency corresponding to a bandwidth of a predetermined radio frequency band a communication apparatus uses; and frequencies of continuous harmonic components of the fundamental frequency for PWM control appear before and after the predetermined radio frequency band.